The predisposition of a river basin to flooding can be assessed months in advance using satellite measurements, according to a study published online in Nature Geoscience. The use of remote observations may ultimately result in longer lead times in flood warnings.
John Reager and colleagues compared river gauge measurements to basin-wide water storage, measured by NASA’s Gravity Recovery and Climate Experiment satellites, leading up to the catastrophic 2011 Missouri River floods. By including satellite information about the total wetness of the river basin from all sources-such as snow, surface water, soil moisture and groundwater-they were able to diagnose the potential for flooding as much as five to eleven months in advance of the 2011 disaster.
In contrast, field measurements of snow water and soil moisture are only useful indicators of flood potential up to two months in advance of a flood event.